Well the model that I have is a 124 300E 1989
so it is not exactly a 126. Also there are no heater problems inside the cars air system as I thought. Everything turns
exactly on time. If there are other possible functions
of the heating line that goes into the reservoir adding a
mechanical valve and regulating it manually might
cause problems elswhere.


The inline thermovalve well yes it is more of a thermoelectrical
valve as itself it is connected only to wires......
I dont believe that it is responsible for maintaining the
engines temperature though. The engine has a thermostat of its own. This heating circuit that I am trying to discuss is somehow separate.The best thing I guess is to equip myslf with a good manual.
I dad similiar problems however with the radiator in a
Fiat while in europe...however it was the thermostat which
was directly on the radiator and was not turning on the electric fans circuit so the radiator would overheat. I believe that in
cars such as mercedes the thermostat is located directly
somewhere on the engine so it measures temp directly.